Distinguishing Feature : A strong smell of garlic emanates from a large clump of Ramsons without ever needing to crush any part of the plant. The stem is 'triangular' in cross-section.
The edible leaves of Ramsons can be eaten in salads, where they impart a garlic-like taste mid-way between that of Leek and
Garlic, or they can be cooked as a vegetable. Both the bulbs and the flowers are also tasty. Be aware that the leaves of Lily-of-the-Valley are very similar to those of Ramsons, but do not smell of garlic when rubbed and are exceedingly poisonous.
Ramsons grow in shady hedgerows or moist deciduous woodland that has some light and quickly out-compete other plants forming a dense carpet of Ramsoms above which the air is infused with a strong smell of garlic.
The flower stem of Ramsons is triangular in cross-section; whereas the leaves have a keel or chevron cross-section.
THE GARLIC ODOUR
It is likely that Ramsons contain the same chemicals as gives Garlic its odour, Allicin and Diallyl Sulfide. Both these sulfur containing compounds are derived from the (only) sulfur containing amino acid, cysteine. Allicin possesses anti-bacterial and fungicidal properties, a defence against attack by pests, but is absent from Garlic until the cloves are crushed when the enzyme allinase (which is present in the cells) is released to convert alliin to allicin. Thus the defence chemical allicin is usefully only deployed when the plant is damaged such as may occur when insects trying to devour Ramsons. Allicin is present in all varieties of Allium including onions.
Although not strictly an amino acid per se, Allicin nevertheless mimics some amino acids in that it can bind to the SH- groups of proteins. Humans are seemingly immune to the effects of allicin, (and it may even proffer beneficial effects) but cattle and horses are not; they can develop haemolytic anaemia (the errant breakdown of red blood cells) by eating garlic or onions and may die as a result. Eating half an onion can kill a horse.
The sulfur containing amino acid is converted into alliin within Garlic (and probably Ramsoms) to be be stored until such time as the plant is damaged, when the enzyme alinase converts the alliin to allicin. When allicin is released it gives the characteristic odour of garlic, and also protects the plant from pests by way of its anti-fungal and anti-bacterial attributes.
Allicin is very a unstable compound and undergoes transformation into any number of both symmetrical and mixed monosulfides, disulfides and trisulfides, many of which contribute to the aroma of garlic or onion. They are volatile and include Dipropenyl-disulfide, Methyl-propenyl-disulfide, Dimethyl-trisulfide, Methyl-propenyl-disulfide, Dimethyl-trisulfide, Methyl-propenyl-trisulfide, Dipropenyl-trisulfide and many others, only some of which are shown below, namely those associated with Ramsons in particular.
Whenever Ransoms grow en-masse in large concentrations the surrounding air is permeated by a strong garlic-like odour, from which the following sulfurous hydrocarbons were identified.
DiMethylDisulfide (DMDS) is an inflammable pale yellow oily liquid with the unpleasant aroma of foetid meat and is the simplest disulfide. DMDS is given off by
Dead-horse Arum (Helicodiceros muscivorus) (which does not occur in the UK) in order to attract flies. It is also used as a garlic-type flavouring in soups and other foodstuffs.
MethylAllysSulfide (or AllylMethylSulfide, AMS) is a liquid with a strong alkyl-sulfurous smell that is produced as a metabolite of garlic and is the volatile responsible for stale odour of 'garlic breath'.
MethylPropenylDisulfide is a pale yellow liquid with a powerful odour which is also used as a allium-like flavouring in foodstuffs.
DipropemylDisulfide may be involved in the anti-cancer properties of Onion. It appears to be the most toxic disulfide to pets and other animals (apart from to humans which can deal with these sulfides); it is an oxidising agent that can cause heamolysis of red blood cells, horses are particularly susceptible - eating half an onion can kill a horse.
PropenylPropylDisulfide is a colourless liquid with an aroma of cooked onions.It is used as a flavouring in foodstuffs.
There are undoubtedly a plethora of other similar sulfur compounds present in the air surrounding Ransoms, sulfides are notoriously active or unstable and can change into other sulfides, sulfonates and thiosulfinates even during chemical analysis.